Rehabilitation approaches to hemineglect.

BACKGROUND: Hemineglect is a difficult neurologic condition to rehabilitate. It arises predominantly from right brain injury, and manifests heterogeneously in clinical deficits such as poor visual exploration to the left, inaccurate assessment of the midpoint of a line, left limb hypokinesis, and anosognosia. Most of the cognitive dysfunction produced by hemineglect is because of an asymmetric distribution of attention, either with respect to extrapersonal space or to an object being viewed. Many treatments draw on hemineglect theory to attempt to mediate the basic asymmetry of attention. REVIEW
SUMMARY: Treatment approaches can be divided into 2 main categories. Extrinsic or "top-down" approaches require active participation of the patient under the guidance of a therapist. The most common approach of this type is visual scanning therapy in which the patient is continually instructed to move the gaze leftward into the neglected space. Intrinsic or "bottom-up" approaches manipulate stimulus characteristics, sensory input, or the brain directly in an attempt to alter the interhemispheral attentional imbalance. Examples of this approach include vestibular stimulation of the left side, sensory activation of the left limb, and transcranial magnetic stimulation of the overactive left hemisphere. Combined approaches such as prism adaptation have also shown good results.
CONCLUSIONS: Hemineglect is a complicated disorder that poses challenges to treatment. A paucity of clinical trial evidence limits our ability to extrapolate experimental mediation of hemineglect to globally improved functioning. Nonetheless, many treatment approaches appear promising. Underlying neuroscience may help guide future treatment approaches.